Related Experiment Video
Updated: Jun 25, 2026
06:18
The Collective Trust Game: An Online Group Adaptation of the Trust Game Based on the HoneyComb Paradigm
Published on: October 20, 2022
Assortment and the evolution of generalized reciprocity
Daniel J Rankin1, Michael Taborsky
1Division of Behavioral Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland. d.rankin@bioc.uzh.ch
Evolution; International Journal of Organic Evolution
|February 19, 2009
Summary
Generalized reciprocity, where individuals help based on past personal experiences, struggles to evolve. However, assortative encounters can promote its evolution, stabilizing cooperation in social dilemmas.
Area of Science:
- Evolutionary Game Theory
- Behavioral Economics
- Social Dynamics
Background:
- Reciprocity is a key driver of cooperation, but direct and indirect forms require complex partner-specific memory.
- Generalized reciprocity relies on simpler, past personal experience, making it potentially easier to implement.
- However, generalized reciprocity struggles to evolve in well-mixed populations against defectors.
Purpose of the Study:
- To investigate the evolutionary conditions favoring generalized reciprocity.
- To analyze the impact of assortment (non-random encounters) on the evolution of generalized reciprocity.
- To determine if generalized reciprocity can be stable in social dilemmas.
Main Methods:
- Mathematical modeling of evolutionary game theory.
- Analysis of a population model incorporating assortment of encounters.
- Examination of the Prisoner's Dilemma and Snowdrift game dynamics.
Main Results:
- Generalized reciprocity cannot evolve in a well-mixed population.
- Assortment of encounters significantly favors the evolution of generalized reciprocity.
- Assortment creates conditions where both indiscriminate cooperation and defection are unstable.
Conclusions:
- Assortment is crucial for the evolution of generalized reciprocity.
- Generalized reciprocity can be an evolutionarily stable strategy under specific conditions of assortment.
- This finding has implications for understanding cooperation in structured populations.
Related Concept Videos
01:28Factors Influencing Attraction IV: Reciprocity
Reciprocity in attraction is fundamental to social and romantic relationships, shaping how individuals form and maintain connections. The psychological principle underlying this phenomenon is that people tend to like those who express liking toward them. Balance theory supports this tendency, suggesting that mutual attraction fosters psychological harmony, whereas one-sided affection leads to discomfort and cognitive dissonance.The Psychological Mechanisms Behind ReciprocityWhen individuals...
01:20Social Foundations of Self II: The Generalized Other
According to George Herbert Mead, as children progress beyond the game stage, they develop a more comprehensive understanding of societal rules and norms. This cognitive and social development enables them to internalize the expectations of the broader community, refining their ability to regulate behavior.Consistent participation in organized activities is crucial in helping children recognize that their actions are not isolated but contribute to a more significant, interconnected group effort.
00:52Social Proof
Social proof is a form of persuasion based on comparison and conformity. People compare their behavior and actions to what others are doing and will change to conform to do what their peers do.
00:57Inclusive Fitness
Most altruistic behavior—in which one animal helps another at a cost to themselves—occurs between relatives. Scientists think these altruistic behaviors evolved because they increase the inclusive fitness of the animal providing help.
01:20Evolutionary Psychology
Evolutionary psychology explores the origins of human behavior and mental processes by framing them within the context of natural selection, a theory famously propounded by Charles Darwin. This field asserts that many behaviors common across human societies — ranging from instinctive fear reactions to complex social interactions — arose as evolutionary adaptations. These adaptations enhanced the survival and reproductive success of our ancestors, thereby becoming embedded in the human psyche...
01:03Altruism
Altruistic behaviors are “unselfish” behaviors—those that help another individual at the expense of the individual carrying out the behavior. Despite the negative consequences for the altruistic animal, these behaviors are thought to have evolved for several reasons.